Which caste to write in documents, fathers or person taking care

Sir/Madam, Since my ssc i had to bear wrong first name and father's name unfortunately . Because of a person who looked after our family after my father expired . He listed his name and initial on my certificates . Now he is not living with us .. I tried so much to change it after a 3 years but i couldn't do it . As there is no option i am carrying his first name and his name as father's name . But the problem is when to get a caste certificate .,it becomes a big problem for me . In some years ago i got the caste certificate as per my own caste i.e Bc- D(his is Bc-b) for education purpose . But now i am going to get caste certificate for employment in govt sector . But i couldn't to decide what caste to mention in that certificate whether my original or his . I want to get it as per my own caste even though his caste gives a bit more reservation in employment . Please guide me in this regard what caste can be correct to mention in the certificate (without any legal problems i